The division of Lutheran command was already giving Charles the expected opportunities. The princes withdrew westward, a palpable confession of weakness. They had been the aggressors, and yet they now surrendered the initiative to Charles. Their retirement enabled the Count of Buren to march in with his Netherland division, and with him the troops of Albert and Hans of Hohenzollern. This march of Buren was the strategic feat of the war. He had led the hostile forces which were watching him a dance up and down the Rhine, and slipped across it unopposed. He had brought his troops three hundred miles, mainly through the heart of Protestant Germany, with no certain knowledge where he should find the Emperor, for communications could only be maintained by means of long detours. Finally he marched boldly past the vastly superior army of the league, which had professedly retired from Ingolstadt to bar his passage.
Charles now took the offensive, pushing the enemy slowly up the Danube, and steadily forcing his way toward Ulm. The strongly Protestant Count Palatine of Neuburg, Otto Henry, was the first prince to lose his territory, which, indeed, his debts had already forced him to desert.
The Lutherans now showed more fight, and during the last fortnight of October the advance came almost to a standstill. Charles was ill, money and supplies were falling short, Spaniards and Italians were suffering from the cold rains of the Danube valley. The papal contingent was demoralized for want of pay; three thousand men deserted in a day, whereas the Lutherans were reënforced. Yet Charles, in spite of professional advice, refused to go into winter quarters. He counted on divisions in the League, on the selfish interests of the towns, on the penury of the princes, and reckoned aright. The fighting was never more than skirmishing; not arms but ducats were deciding the issue; the fate of war was literally hanging on a fortnight's pay.
The Emperor had said that a league between towns and princes could never last. The financial burden pressed mainly on the cities, and they refused to raise further subsidies. The richer classes had always disliked the war; the great merchants were often, as the Fuggers of Augsburg, zealous Catholics. Trade was at a standstill, and they could protest that all their capital was at the Emperor's mercy, at Antwerp, at Seville, in the Indies, or else in Portugal. It was convenient to forget the brisk traffic which still continued with friendly Lyons. Zeal for the Lutheran cause seemed limited to a Catholic, Piero Strozzi the Florentine exile, who in his hatred for the Hapsburgs was vainly spending his fortune on revenge, striving for aid from Venice, negotiating loans from France. There was, moreover, no real solidarity between Northern and Southern Germany. Neither the Protestant princes nor the wealthy cities of the Baltic had as yet stirred a finger for the cause. Under any circumstances the Lutheran army must have broken up. The leaders had resolved to retire to the Rhineland for the winter, live at free quarters on the ecclesiastical princes, and renew the struggle in the spring.
At this critical moment Maurice of Saxony came into action. Hitherto his conduct had been ambiguous. This was probably due less to deliberate deceit than to genuine hesitation. The incompetence of the Lutheran leaders and Ferdinand's expressed intention of invading Ernestine Saxony determined him. Persuading his estates with difficulty that it was necessary to save the Electorate for the house of Wettin, he undertook to execute the ban in his cousin's state. His reward was the title of elector and the Ernestine territories. The correspondence of Charles and his brother on the subject was characteristic of both. Ferdinand, always greedy of territory, had bargained for partition, but Charles persuaded him to be content with John Frederick's Bohemian fiefs.
Charles, cautious and suspicious, was unwilling to grant the title until Maurice had proved his loyalty; Ferdinand, more impetuous, induced him to pay the bribe and give credit for the service. The Albertine and Austrian troops soon overran the defenceless land. This determined the manner of the Danubian campaign, and the Saxon phase of the war began. John Frederick must withdraw his troops to defend their homes, and he plundered en route the neutral ecclesiastical territories through which he passed. "In a papal country," he told the burgomaster of Aschaffenburg, "there is nothing neutral." The campaign of the Danube was suddenly over. Philip of Hesse retired sullenly to his two wives, as Schartlin put it. As he passed through Frankfurt he hoisted banners with the crucifix, flails, and mattocks, to incite the lower classes to revolt; he had failed to bend the powers above him, he would fain stir Acheron.
Charles could now complete the subjection of Southern Germany. Granvelle, the last to be convinced of the necessity of war, was the first convert to the policy of peace, which the Landgrave and the towns desired. Peace would relieve the financial strain and prevent the Germans from becoming desperate; peace would enable Charles to turn his arms against the Turks. Charles thought it undignified to negotiate with an army in the field: peace entailed the abandonment of Maurice, and henceforth no other prince would dare serve him; Augsburg and Ulm, if they were persuaded that he had no wish to establish a tyranny in Germany, were likely to capitulate, and after a victory his generosity in leaving Germany her liberty would appear the greater. Charles did not at this moment fear the Turk, and it was in his power at any moment to propitiate the French. Pedro de Soto urged the continuance of the war, to avert the danger of a papal-French combination, which would be the natural result of Paul's indignation at a compromise with heretics.
The deserted princes and towns of South Germany now one by one made submission. Very pathetic was the Emperor's meeting with the Elector Palatine, the friend of his youth, the whilom lover of his sister, the husband of his niece. Charles did not extend his hand: the Elector made three low bows, after which Charles drew out a paper which he read and then spoke to him in French—"It has grieved me most of all that you in your old age should have been my enemies' companion, when we have been brought up together in our youth." The Elector answered almost in a whisper, and left "like a skinned cat," the Emperor half raising his cap, but no one else. He was ordered to go to Granvelle, and the minister played the doctor and healed the wound. He returned with tears in his eyes, and then Charles forgave him. "My cousin, I am content that your past deserts toward me should cancel the errors which you have recently committed." Henceforth the old friendship was renewed.
Ulrich of Wuertemberg escaped less lightly. He paid a large indemnity, received Spanish garrisons in his fortresses, and engaged to serve against his late allies. He had no resource, for his subjects hated him; from the windows of the cottages fluttered the red and white Burgundian colors as a token of what was in the peasants' hearts. Ferdinand pressed warmly for the restoration of the duchy to Austria, but Charles replied that the aim of the war was the service of God and the revival of imperial authority: to seek their private advantage would only quicken the envy with which neighboring powers regarded the house of Hapsburg. Farther north the octogenarian of the Elector of Cologne resigned his see, and the evangelization of the Middle Rhine was at an end. Ulm gave in with a good grace, but Augsburg long delayed. Charles' original intention was, apparently, to garrison these towns, as Milan and Naples, with reliable Spanish troops, and perhaps to destroy their walls and dominate them by fortresses. But he treated the cities leniently. He left here and there companies of imperial troops, levied moderate contributions, replaced at Ulm and Augsburg the democratic constitution of the trades by the old wealthy aristocracies, but promised to respect the existing religion. Strasburg, which, in spite of French entreaties, capitulated in February, 1547, was almost exempt from punishment; it was feared that the distant, wealthy, and headstrong city might hold out a hand to the Swiss and become a canton.
In Southern and Western Germany there was no longer an enemy in the field, but, in the North, Maurice's treachery had brought its penalty. John Frederick, acting with unusual vigor, recovered his dominions, received homage from the feudatories of Halberstadt and Magdeburg, and overran Maurice's territories, until he was checked before the walls of Leipsic. When Ferdinand prepared to aid Maurice, the German Protestants of Lusatia and Silesia refused their contingents, and the Bohemian Utraquists made common cause with the Lutherans. The Utraquist nobility and towns formed a league in defence of national and religious liberties; they convoked a diet and raised an army. Ferdinand was faced by a general Bohemian revolt. His position was weakened by his wife's death in February, for it was pretended that he was merely consort. Only the Catholic nobles were for the Hapsburg King; the roads were barricaded to prevent the passage of his artillery; and John Frederick, entering Bohemia, received a hearty welcome. The North German maritime and inland cities were now in arms, and the Lutheran princes of Oldenburg and Mansfield were threatening the Netherlands. Charles sent his best troops to Ferdinand's aid, and despatched Hans and Albert Hohenzollern in support of Maurice. But Germans could still beat Germans. Albert was surprised and taken at Rochlitz. Ferdinand eagerly pressed Charles to march north in person. The Emperor was unwilling, and Granvelle strongly dissuaded it. The despatch of Alba was the alternative, but Charles did not trust his generalship. He was delayed, partly by gout, and partly by fear of a fresh rising in the Swabian towns. Here he had left seven thousand men, but he could not himself safely stay in Nuremberg without a garrison of three thousand, and could not afford to lock these up. His sole presence in the North, wrote Piero Colonna, was worth twenty-five thousand foot, and Charles, ill as he was, must march.